I can relate a lot to this. I am fairly new to poly and so is my main partner but she is very comfortable with expressing herself and making deep connections with people. I am not to say the least. I felt bad that I wasn't being "successful" at finding someone else until I stopped to realize I didn't need to find someone. A goal of being poly is being free to be as happy as possible. I know that it is difficult for some or to maintain all the time but I am happy "dating" myself. Having my main partner also makes me happy. I don't need anyone else to help me be happy because I already have love from myself as well as from someone else. Now, with time, if I do find someone I'm comfortable with I can pursue that relationship too. For me to get out of that "successful" mind set I had to come with terms that I'm already there. I'm happy that my partner has found someone because now they're even happier and I get to see them smile even more.

So tldr: if you can be happy with yourself and happy with yourself and your partner, then the goal should be to focus on those IMO.